Automatic change-over and indicator valve



Dec. 11, 1951 A. w. CHANDLER AUTOMATIC CHANGE OVER AND INDICATOR VALVE 2 SHEETS-Sl-iE-ET 1 Filed Nov. 26, 1948 W6 ym RR 8 L m V WM C A ATTORNEYS Dec. 11, 1951 A. w. CHANDLER 2,578,042

AUTOMATIC CHANGE OVER AND INDICATOR VALVE Filed Nov. 26, 1948 2 SHEETS-SHEET 2 Fla. 5

EMPTY 53 70A I 76A/ 70 67 7a 76 W 83 7 80* K 75 r l IN V EN TOR.

A.WCHANDLER A TTORNE YS PatentedDec. 11, 1951 AUTOMATIC CHANGE-OVER AND IND ICATOR VALVE Alanson W. Chandler, Bartlesville, kla., assignor to Phillips Petroleum Company, a corporation oi Delaware Application November 26, 1948, Serial No. 61,937

Claims.

This invention relates to a dispensing system for high pressure fluids and includes a device for automatically changing withdrawal connections from a plurality of sources. In one of its more specific aspects it relates to a fully automatic changeover device for the transfer of withdrawal connections from one source of high pressure gas to another upon descrease in pressure from the first source. In a still more specific aspect it relates to a fully automatic changeover and cylinder indicating assembly for the transfer of withdrawal connections from one source of high pressure gas to another upon decrease in pressure from the first source with the indication of which source of gas is depleted.

In dispensing fluid under pressure from containers as. for example, liquefied petroleum gas, a devicefor automatically changing withdrawal connections from one container to another is desirable to insure an uninterrupted flow of the fluid. Various semi-automatic and fully automatic changeover devices have been proposed heretofore. The purpose of my invention is to provide a dispensing system includin an improved fully automatic changeover device which possesses several desirable characteristics which will be realized upon reading the following specification.

An object of my invention is to provide an im proved changeover device which is fully automatic and of simplified construction while being efficient and positive in its operation. A further object of my invention is to provide an automatic changeover device which is composed of a minimum number of parts. and depends for its operation on decrease in pressure from a supply source. Another object of my invention is to provide a changeover device for liquefied gas dispensin systems which will give visual indication as to which of the two sources of gas is being used. Still another objectof my invention is to provide a fully automatic changeover device for liquefied gas dispensing systems which will give visual indication as to which of two sources of gas is being used and for use in conjunction with a device to indicate visually when one tank is empty and further to indicate visually which tank is empty. Yet another object of my invention is to provide an automatic changeover device which is entirely enclosed, thereby making the device fool-proof. Many other objects and advantages of my changeover device will be realized upon reading the following disclosure, which, taken with the attached drawing, forms a part of this specification.

shows, in part, an LPG dispensing system with my automatic changeover device. Figure 5 is a longitudinal view, partly in section and partly in elevation, of the empty drum" indicating portion of my apparatus. Figure 6 is a cross sectional'view of the apparatus taken on the line 6-6 of Figure 5. Figure 7 is a side elevational view, in part, showing the indicator windows with the indicating arrow carrying the word Empty in a position indicating that neither tank is. empty.

Referring now to Figure 1, my changeover device is composed of a main body member II which, as illustrated in the drawing, is substantially square in cross-section. An end body member l2 in more or less the form of a cap covers one end of this main body housing II. A similar cap or end member l3 covers the other end of the body housing I I. These two caps may be attached to the main body member by means of some screws or bolts it through holes in flanges l4 and I5. Between the cap member l2 and the body member I l is disposed a diaphragm I! as shown. A similar diaphragm I8 is disposed at the other end of the apparatus between the cap member 3 and body member II. The cap member I2 has a threaded high pressure gas inlet opening 2| in its center and this opening terminates in the form of a circular valve seat 23. On one side of the cap member I2 is a gas outlet opening 25 which is threaded for accommodation of a pipe fitting. The other cap member l3 also has a threaded inlet opening 22 in its center and this opening terminates as a valve seat 24. A gas outlet opening 21 has threads 28 for accommodation of an outlet pipe fitting. The cap members l2 and I3 with their respective diaphragms I! and I8 form pressure chambers 19 and 2|], respectively. The portion of the apparatus between the two diaphragms is open to the atmosphere through opening 20' and therefore contains no gases under pressure. The diaphragm member I! is fitted with a holder 36 which is rigidly attached by threads to one end of a push rod or cross member 3|. This member 35 is intended to fit tightly against one side of the diaphragm I! while a circular stop mem ber 38 is heldtightly against a shoulder on the push rod 3| and tightly against the back side of the diaphragm H. In this holder 38 is disposed a disk shaped resilient member 23 which is adapted to form a gas tight seal against the valve seat 23 when the diaphragm I1 is pushed or moved toward the right in Figure 1.

In like manner, the diaphragm |8 in the opposite end of the changeover is fitted with a sealing member holder 31 containing a resilient sealing member 30. The stop member 39 is. rigidly held against the push rod shoulder upon screwin the sealing member holder 3'! into place on its end of the cross member 3|. This resilient sealing disk 38 is intended to form a gas tight seal with the valve seat 24 at such times as when diaphragm 8 is moved to the left in Figure 1.

Since the diaphragms I! and i8 are rigidly fastened to the ends of the cross member 3| these two diaphragms are immovable with respect to each other. But, of course, the entire push rod-diaphragm assembly is movable longitudinally.

The indicating device of the changeover portion of my apparatus is composed of an indicator arm 34 pivoted at 33 and held in position by stops 32. On the free end of the indicator arm 34 is an indicator arc member 35 on which are placed arrows 40 and 4|. From this construction it will be seen that when the diaphragm-cross member assembly is moved to the left the indicator are 35 also travels to the left, which movement places the arrow 48 directly behind a window 42, see Figure 3. Likewise, when the cross member diaphragm assembly moves toward the right the indicator are 35 will move toward the right and arrow 4| will take its position in the window 42 of Figure 3.

On reference to Figure 2, which shows another view of this indicator assembly, the indicator arc 35 is shown directly behind the window 42 and the pins 32 are shown attached to the cross member 3| for moving the indicator arm 34.

In Figure 5 is illustrated the empty drum indicating apparatus part oi my invention. This indicator consists of a housing 66 having an opening 61 at one end as shown. Covering this opening is a cap 68 into which may be inserted a pipe 86 shown in Figure 4. Between this cap and the opening 61 is a diaphragm 69 which is attached to one end of a cross rod 19 and held in place by a spring plate 10, a shoulder plate A and a nut 12. A light weight spring ii is inserted as shown between the inlet opening of the cap 68 and the compression spring plate 10. In the other end of the housing 66 is an opening 13 similar to opening 61. This openin 73 is covered also by a diaphragm and a cap 14. This diaphragm is is held in place by a spring plate 16, a shoulder plate 16A and a nut 18. The compression spring i1 is positioned in this end of the assembly similar to the positioning of spring H in the other end. An indicator arm 80 pivoted to the cross rod 19 at 8| is held in place b pivot 82. The pivot point 82 is the center of rotation of this indicator arm 8|]. To the free end of the indicator arm 88 is attached an indicator plate 83 on which is Written the word Empty. This construction is such that when the cross rod 19 moves toward the left the indicator 83 moves toward the left and similarly when the cross rod 19 moves toward the right this indicator also moves toward the right and when there are equal pressures under the caps 68 and 14 the compression springs II and 11 hold the indicator 83 in a central position as illustrated in Figures 5 and 7. In Figure 6 is illustrated positioning oi the indicator assembly within the housing 88. The pivots 8| and 82 are shown in their relation to the push rod 18 and the housing 68. The indicator 83 is shown between windows 84 and 85. Figure 7 shows the side view, in part, oi. this Empty" indicator assembly and shows speciflcally the windows 84 and 85 through which the word Empty" may be seen when the indicator arm 8|) is in certain positions.

Figure 4 shows the assembly of my changeover device in an LPG system in which tanks 5| and 52 contain liquefied petroleum gas under pressure. These tanks are fitted with outletvalves 53 and 54, to which are connected delivery lines 55 and 58, respectively. Delivery line 55 is attached to the threaded opening 22 in the changeover and the deliver pipe 58 is attached to the threaded opening 2|, as shown in Figure 1. A gas outlet line 62 is attached to the threaded outlet opening 21 in this line is fitted a check valve 51. A gas outlet line 63 is attached to the other outlet opening and this outlet line is equipped with a check valve 58. These two outlet lines 62 and 63 terminate in a T 59. The outlet side of the T 59 is attached to a line 6| which contains a pressure reducing valve 60. Line 6| conducts gas on to the gas burning appliances.

Also in Figure 4 is shown the positioning of the Empty indicator assembly 65 in relation to the changeover portion of my apparatus. As mentioned hereinbefore, the line 85 connects with the delivery line from cylinder 5| and line 81 connects with the gas delivery line 58 from cylinder 52. When valve 53 in cylinder 5| is open whatever pressure is in cylinder 5| will be communicated through line 86 to diaphragm 69, and similarly whatever pressure is in cylinder 52 will be communicated through lines 58 and 81 to diaphragm 75 when valve 54 is open.

In the operation of my changeover device, as the device is illustrated in Figure 1, high pressure gas is entering the pressure chamber l9 throu h the line 56 from the cylinder 52. From the chamber I9 then the gas leaves by way of the outlet pipe 63 and passes through the check valve 58, the T 59, the pressure reducer and on through line 6| to the appliances. In this particular operation the pressure of the cylinder 52 is communicated into the entire space of the pressure chamber is and this pressure acts on the entire surface of the diaphragm I! to push the diaphragm-cross rod assembly from the right to the left of Figure 1 and in so doing the valve 23 is open and the resilient seal member 38 is held firmly against the valve seat 24 and that valve then closes off any possible gas flow from the cylinder 5|. Even though the valve 53 in cylinder 5| is open and the high pressure from the cylinder is communicated through pipe 55 to a portion of the resilient surface 30, the valve 24 still remains closed. As long as some liquid is in each of the cylinders 5| and 52 the pressures of the gas per square inch acting on the resilient member 30 and on the diaphragm I! in pounds per square inch ,are equal, but the valve assembly phragm H from the cylinder 52. When this condition occurs the diaphragm-cross member assembly will move from left to the right and this movement accordingly opens the pressure chamber 20 to the full gas pressure from cylinder 5| while the resilient member 29 is pushed firmly against the valve seat 23 to close off the pressure chamber l9 from the gas pressure of cylinder 52. The movement of the diaphragm-cross member assembly from left to right and right to left is substantially snap-action in character. For example, movement is started from left to right, the seal at valve 24 is broken and high pressure gas from tank 5| then acts over the entire area of the diaphragm l3 and movement is then rapid.

During the time gas is flowing from cylinder 52 through pressure chamber I9 and through outlet line 63 and the diaphragm-cross member assembly is moved to the left and the arrow 40 with the head pointing to the right is behind the window and the direction of this arrow indicates the gas is coming. from the right, that is, from cylinder 52.

When the diaphragm-cross member assembly moves to the right to close of! cylinder 52 and to open cylinder 5| to the line, then the arrow 4| moves into position behind the window 42 and this arrow points in the direction of cylinder 5| which is then supplying gas to the system.

By connecting the lines 85 and 81 on the cylinder side of valves 23 and 24 of the changeover assembly, the Empty indicator will always be under the pressures of the two cylinders regardless of what these pressures might be, thus when cylinders 5| and 52 contain liquefied gas, pressures will be normal working pressures and regardless of whether the changeover valve in assembly has cylinder 5| closed or opened the full tank pressure will be transmitted through pipe 86 to that end of the Empty indicator assembly. When cylinder 5| becomes depleted of its liquid contents the pressure under t e cap 58 decreases and the full pressure of cylinder 52 acting under the cap 14 and on diaphragm 15 accordingly moves the cross rod with its attached indicator arm 30 to the left and the word Empty then appears behind the window 84. In like manner, as cylinder 52 became empty through use and cylinder 5| had been replaced by a full cylinder of liquefied gas, the indicator 83 carrying the word Empty would move from its central position to a point directly behind the window 85, thus indicating that cylinder 52 had become exhausted.

In installing my changeover device, it is preferable to connect the two gas outlet lines 62 and 63 to the threaded openings 21 and 25, respectively, first. The gas delivery lines 55 and 56 from the two cylinders are then connected to the respective threaded openings 22 and 2|. However, this procedure is not critical since the delivery lines 55 and 56 m y be connected first, if desired. Of course, while making all of these connections, the valves 53 and 54 of the two cylinders are maintained clcs d. During the time the changeover device is not in use the diaphragm push rod-assembly may be to the left or to the right, or in a central position, depending upon its former use. If this apparatus is new. the diaphragm-cross member assembly will probably be in a central position and the proportion of the indicator are between the two arrows 40 and 4| will be directly behind the window 42. When the device is fully connected to the dispensing system, as stated hereinbefore, if cylinder 5| is open to the line the diaphragm-cross member assembly will immediately move to the right opening cylinder 5| to the line and closing oil the cylinder 52 at the valve 23. After the diaphragmcross member assembly has moved to the right, which movement requires only a very short time as, for example, a fractionof a second, the valve 54 may be opened thereby putting the pressure of tank 52 against the resilient member 29. As explained herelnbefore since the force acting against the entire surface of diaphragm I3 is greater than the entire force acting against the resilient member 29 from tank 52 this diaphragm assembly will stay in this position until such time as the liquid has all evaporated from cylinder 5| and the pressure in this cylinder is materially decreased. At that time the diaphragm assembly will move from the right to the left opening tank 52 to the line.

The check valves used in this system should be of good design and construction so as not to permit leakage from the high pressure side into a pressure chamber. Leakage at this point might hold the diaphragm-cross member assembly in an intermediate position permitting gas from both cylinders 5| and 52 to be drawn upon.

Thus it .will be seen by use of my combination device as hercinbefore disclosed the apparatus will indicate whi 'h of the two tanks is presently in use and it will also indicate which tank, if ei her, is empty.

If the empty indicator in assembly 55 is in a central position opcratively, the indication is that both cylinders are full or both cylinders are empty. If both cylinders are full, then upon reference to assembly Hi the particular tank being in use is indicated while if both tanks are empty the indicator 35 in assembly ill will indicate which tank was last withdrawn from.

While I have illustrated and explained the changeover device as being a long and square shaped device, this particular form is not necessary since, if desired, the housing I I and the caps l2 may be of circular cross section. If the device is of circular cross section, thenthe indica' or arm 34 may preferably be horizontally disposed with the pivot 33 located at point 64. The pins 32 will extend vertically upward from the cross member 3| and the indicator are 35 may then be attached at right angles to the free end of the arm 34. The window 42 will then be approximately in the cent r of the sidewall of the body member The diaphragms and resilient members 29 and 3|] and all other parts of my apparatus need not be constructed of special material but may be constructed of standard materials available commercially. The resilient members 29 and 30 may be of a hydrocarbon-resistant synthetic rubber or any sim ilar resilient material adapted for forming a tight seal against the metal valve seats 23 and 24. Diaphragms of many sizes and for all operating pressures are commercially available. The indicator arrows 40 and 4| may well be painted white or white enameled or of some other colors which are easily visible, even in subdued light.

The empty assembly may be rectangular in cross section with the caps 68 and I4 square. These caps and the diaphragms may be circu lar in section, if desired.

In still another embodiment, the chang-eover" and the empty member of my assembly may be included within a common body member to ma"e the apparatus compact.

It will be obvious to those skilled in the art that many variations and alterations of my apparatus may be made, some of which have been suggested, and yet remain within the intended spirit and scope of my invention.

Having disclosed my invention, I claim:

1. In a liquefied gas system, an automatic indicating changeover valve assembly comprising in combination a body member provided with an inlet port and an outlet port for each of two supply sources,. a pressure responsive diaphragm associated with each of said inlet ports, one each 01' said diaphragms fixed at opposite ends of a movable cross member and each diaphragm immovable with respect to the other diaphragm, a chamber bounded by said diaphragms on either end and surrounded by said body and the body surrounding this latter chamber having an opening therein for communication between this chamber and the atmosphere, and a pressure chamber formed by each of said diaphragms on the inlet port side thereof. a valve sealing member associated with each diaphragm on the pressure chamber side thereof, one each of said inlet ports terminating in one each of said pressure chambers as a valve seat, each of said valve sealing members so positioned as to close the adjacent inlet port when the force applied to the diaphragm adjacent said inlet port is less than the force applied to the other diaphragm, and an indicator pivoted to said body member and movably attached to said movable cross member to indicate the open inlet port.

2. In a system for dispensing liquefied gas consisting of two containers for the liquefied gas, a gas delivery line from each container, 9. check valve in each of two outlet lines, said two outlet lines being in fluid communication with a pressure reducing valve and said pressure reducing valve on its outlet side being connected with a line for deliverim; gas to appliances, and an automatic changeover valve assembly connected with said two gas delivery lines and with said two outlet lines communicating with said pressure reducing valve, said automatic changeover valve comprising in combination a body member provided with an inlet port connected with one each of said gas delivery lines, and provided with an outlet port connected with one each of said lines fitted with said check valves, a pressure responsive diaphragm associated with each of said inlet ports, one each of said diaphragms fixed at opposite ends of a movable cross member and each diaphragm immovable with respect to the other diaphragm, and a chamber bounded by said diaphragm on either end and surrounded by said body and the body surrounding this latter chamber having an opening therein for communication between this chamber and the atmosphere, a pressure chamber formed by each of said diaphragms on their respective inlet port sides, said outlet ports disposed also on the inlet port sides of said diaphragms, a valve sealing member associated with each diaphragm on the pressure chamber side thereof, one each of said inlet ports terminating in one each of said pressure chambers as a valve seat and each of said valve sealing members so positioned as to close the adjacent inlet port when the force applied to the diaphragm adjacent the inlet port to be closed is less than the force applied to the other diaphragm; and an indicator arm having one end pivoted to said body member, said arm being movably attached to said movable cross member and being adapted to move therewith to indicate the open inlet port.

3. An indicating changeover liquefied gas dis- 8 pensing system comprising, in combination, a pair of containers for storing liquefied gas, a gas delivery pipe from each container to one side of an indicating automatic changeover, a gas outlet line from each side of said automatic changeover to the inlet side of a pressure reducing valve, each of said gas outlet lines carrying a check valve, a line connected with the outlet side of said pressure reducing valve to conduct gas to an appliance, said automatic changeover comprising in combination a body member provided with an inlet port for connection with one each of said gas delivery lines, an outlet port for connection with one each of said gas outlet lines, a pressure responsive diaphragm associated with one each of said inlet ports, one each oi. said diaphragms fixed at opposite ends of a movable cross member and each diaphragm immovable with respect to the other diaphragm, a chamber bounded by said diaphragms on either end and surrounded by said body and the body surrounding this latter chamber having an opening therein for communication between this chamber and the atmosphere, 8. pressure chamber formed by each of said diaphragms and said body member on their respective inlet port sides, said outlet ports disposed also on the inlet port sides of said diaphragms, a valve sealing member associated with each diaphragm on the pressure chamber side thereof, one each of said inlet ports terminating in one each of said pressure chambers as a valve seat and each of said valve sealing members so positioned as to close the adjacent inlet port when the force applied to the diaphragm adjacent the inlet port to be closed is less than the force applied to the other diaphragm; and an indicator arm having one end pivoted to said body member, said arm being movably attached to said cross member and being adapted to move therewith to indicate the open inlet port.

4. An indicating changeover and storage, liquefied gas dispensing system comprising, in combination, a pair of containers for storing liquefied gas, a delivery pipe from each container to one side of an automatic indicating changeover, said delivery pipe from each container also connected to one side of a storage indicating assembly, a gas outlet line from each side of said automatic changeover to the inlet side of a pressure reducing valve, a check valve in each of said gas outlet lines, a line connected with the outlet side of said pressure reducing valve to conduct gases to an appliance, said automatic indicating changeover comprising in combination a body member provided with an inlet port for connection with each of said gas delivery lines, an outlet port for connection with each of said gas outlet lines, a pressure responsive diaphragm associated with each of said inlet ports, one each of said diaphragms fixed at opposite ends of a movable cross member and each diaphragm immovable with respect to the other diaphragm, a pressure chamber formed by each of said diaphragms and said body member on their respective inlet port sides, said outlet ports disposed also on the inlet port sides of said diaphragms, a valve sealing member associated with each diaphragm on the pressure chamber side thereof, one each of said inlet ports terminating in one each of said pressure chambers as a valve seat and each of said valve sealing members so positioned as to close the adjacent inlet port when pressure is applied through the other inlet port to its pressure chamber the force applied to the diaphragm adjacent the 75 inlet port to be closed is less than the force ap- I 9 plied to the other diaphragm, an indicator arm pivoted at one end to said changeover body member and said arm is pivotally attached 'to said movable cross member and is adapted to move therewith to indicate the open inlet port; said storage indicating assembly comprising in combination, a housing having a pressure inlet port connected with each of said gas delivery lines, a pressure responsive diaphragm associated with each of said inlet ports, one each or latter said diaphragms fixed at opposite ends of a movable cross rod and each of said diaphragms immovable with respect to the other diaphragms, a pressure chamber formed by each of said diaphragms on their respective pressure inlet port sides, a spring disposed between each diaphragm and its respective pressure inlet port, an indicator arm pivoted at one end to said storage indicating assembly body and said arm is pivotally attached to said movable cross rod and is adapted to move therewith in the direction of the diaphragm exposed toa pressure lower than the pressure exposed to the other diaphragm.

5. In a liquefied gas system, a completely automatic changeover'valve mechanism comprising in combination a body member and two pressure responsive diaphragms, said-diaphragm being disposed in said body member so as to divide said body member into two terminally dispoud pressure chambers and a centrally disposed chamber. said diaphragms being rigidly interconnected by a longitudinally movable cross member; each of said pressure chambers having an inlet port terminating as a valve seat, and an outlet port;' and each of said diaphragms having associated therewith a resilient valve sealing member disposed in cooperative relationship with one of said valve seats so as to close one valve when the force applied to the diaphragm of the valve to be closed is less than the force applied to the other diaphragm; and an indicator arm having one end pivoted to said body member, said arm being movably attached to said movable cross member and being adapted to move therewith to indicate the open inlet port.

ALANSON W. CHANDLER.

REFERENCES CITED The following references are of record in the file 0! this patent:

UNITED STATES PATENTS Number Name Date 1,858,291 Burdett May 17, 1932 2,126,355 Thomas Aug. 9, 1938 2,318,261 St. Clair May 4, 1943 2,354,286 Whaley July 25, 1944 

